Field of the Invention
The disclosure relates to gravure offset printing, and in particular it relates to a blanket of the gravure offset printing.
Description of the Related Art
Printed electronic products possess great market potential. There is a continuing goal to miniaturize. To satisfy the design requirements of lighter, smaller, or thinner products, the volume of each component utilized in the product is strictly limited. Taking conductive wires—the most common component in printed electronic products—as an example, the line width thereof is reduced from the hundred-micron scale to a scale of just several microns. Screen printing is typically used in the manufacture of traditional conductive wires. However, the mass-producible line width is only down to 70 μm due to the intrinsic limitations of the screen. Obviously, such a process capability is insufficient for processing currently popular touch panels. To achieve fine wire production, most manufacturers rely on photolithographic technology. Although this process can produce wires with a line width less than 10 microns, the production cost is significantly higher than that of the printing process. Moreover, this process is not environmentally friendly because of the huge consumption of energy and materials.
To meet the production capacity of thin conductive paths and manufacturing cost considerations, gravure transfer (gravure offset printing) technology has seen a lot of research and trial production in industry in recent years, but the blanket of the gravure offset printing still needs to be improved. For example, a paste transfer layer of a blanket for the gravure transfer may swell due to long-term contact with the solvent in the paste. The swelled paste transfer layer may negatively influence the line width uniformity of the transferred paste, and even degrade the conductivity of a whole substrate with the transferred paste thereon. In addition, the swelling problem may shorten the product lifespan of the blanket, thereby increasing the processing cost. Fluoroelastomer has been selected to serve as a paste transfer layer by some skilled in the art to solve the above swelling problem. However, the phenomenon of the paste transfer layer absorbing solvent is a necessary phenomenon during the gravure transfer. If the paste transfer layer is entirely composed of the fluoroelastomer, it cannot effectively absorb the solvent and therefore lowers the transfer quality.
Accordingly, a novel blanket to solve the above problems is called for.